Cant login to my wp-admin after switching to SSL

I recently changed my wordpress site from http to https and now I can't login to my wp-admin.

It just refreshes the page and I am not logged in.

Is there something I forgot to change in my wordpress files?

I inspected the code and the login form is pointing to my old site (the http one) and when I look at the code in the file, the form action is set to site_url() and I cant seem to find where its defined.

You need to change the site url in wp-admin->Settings->General. Except now you need to go in through phpMyAdmin and do it manually in the wp_options table since you are locked out.

You get different cookies depending on http/https so you are getting the https cookie and then being redirected to http that has no cookie because of your Wordpress settings that say what url the site resides at.